1. Field of the Invention
The present invention relates to a rotary bar screen device, and more particularly, to a rotary bar screen device with an increased effective area, for maximizing the effective area for passing seawater and simply and conveniently picking up and removing foreign materials such as floating matters from water.
2. Description of the Related Art
In general, a seawater refreshing plant or an electricity generating plant is equipped with a rotary bar screen device at its water intake port to filter a shellfish or an oceanic life and foreign materials such as various floating waste materials out of seawater because it takes and uses the seawater as a raw water or a cooling water of a cooling system.
FIG. 1 illustrates a conventional rotary bar screen device. As shown in FIG. 1, a support frame 10 is installed in a concrete structure of a water intake facility, and driving sprockets 30 are installed at both sides over the support frame 10, and driven sprockets 32 are installed at both sides under the water intake facility. The sprockets 30 and 32 connect with each other by a transfer chain 40, and the transfer chain 40 is equipped with a screen bucket 50.
The conventional rotary bar screen device operates in such a manner that the screen bucket 50 installed at the transfer chain 40 picks up various foreign materials from the water and elevates the foreign materials on its movement the moment the transfer chain 40 circulatively moves by activating the driving sprocket 30 using a driving source such as a motor 20, and the foreign materials fall down and are collected by the collection tub 80 as the screen bucket 50 turns over passing a top point of the driving sprocket 30.
However, the conventional rotary bar screen device is incliningly installed to more smoothly drop the foreign materials because the foreign materials are filtered by the screen bucket 50 and are broken away from the screen bucket 50 simply by a self-weight after being transferred to an upper part of the driving sprocket 30. Accordingly, the conventional rotary bar screen device has a drawback that it excessively occupies a space for installation in a water intake structure, and has a considerable difficulty in a maintenance work.
As shown in FIGS. 2 and 3, the screen bucket 50 is of a structure in which the bar block 55 is installed by a fixing bolt in a space between a pipe shaped upper bar 51 with a predetermined height and a channel shaped lower bar 52 horizontally with the direction in which the seawater flows. Therefore, the screen bucket 50 necessarily requires a separate bracket 57 for installing and fixing the bar block 55 between the upper and lower bars 51 and 52 between which the seawater is introduced. Accordingly, there is a drawback of sufficiently guaranteeing an introduction passage for passing the seawater. In other words, an effective height (h2) of a through-hole 54 for introducing the seawater is merely about 61% of a total height (h1) of the screen bucket 50.